Hearing aids are electronic instruments that compensate for hearing losses by amplifying sound. The electronic components of a hearing aid include a microphone for receiving ambient sound, an amplifier for amplifying the microphone signal in a manner that depends upon the frequency and amplitude of the microphone signal, a speaker for converting the amplified microphone signal to sound for the wearer, and a battery for powering the components. In certain types of hearing aids, the electronic components are enclosed by housing that is designed to be worn in the ear for both aesthetic and functional reasons. Such devices may be referred to as in-the-ear (ITE), in-the-canal (ITC), completely-in-the-canal (CIC) type, or invisible-in-the-canal (IIC) hearing aids. Other types of hearing aids, referred to as receiver-in-canal (RIC) hearing aids, include a receiver housing that is worn in the ear.